Two classes of polyfluorinated quaternary ammonium salts have been described in the literature. Thus, U.S. Pat. No. 2,727,923 claims products of the formula EQU [C.sub.n F.sub.2n+1 -CH.sub.2 -- NR.sub.1 R.sub.2 R.sub.3 ] + X.sup.-
in which n is an integer between 3 and 9. These products are obtained by reduction of the amide EQU C.sub.n F.sub.2n+1 - CO - NR.sub.1 R.sub.2
followed by the reaction of the amine EQU C.sub.n F.sub.2n+1 - CH.sub.2 - N R.sub.1 R.sub.2
with the compound of the formula R.sub.3 X. R.sub.1, R.sub.2 and R.sub.3 are alkyl radicals containing from 1 to 5 carbons. X represents bromine, iodine, chlorine, fluorine or the hydroxyl group.
On the other hand, U.S. Pat. No. 3,257,407 claims ammonium salts of the formula EQU [C.sub.n F.sub.2n+1 (CH.sub.2).sub.m NR.sub.3 R.sub.4 R.sub.5 ] + X.sup.-
in which n is between 3 and 20, m is between 3 and 30 and and NR.sub.3 R.sub.4 R.sub.5 represents a radical derived from ammonia or pyridine. The patentee asserts that the quaternary ammonium salts EQU [C.sub.n F.sub.2n+1 - CH.sub.2 - CH.sub.2 - NR'R"R'"] + X.sup.-
cannot be synthesized from the iodides of the polyfluoroalkanes EQU C.sub.n F.sub.2n+1 - CH.sub.2 - CH.sub.2 I
because the latter are deiodohydrogenated by the tertiary amines in accordance with equation (4). EQU C.sub.n F.sub.2n+1 - CH.sub.2 - CH.sub.2 - I .sup.NR'R"R'" C.sub.n F.sub.2n+1 -CH = CH.sub.2 ( 4)